Displays such as CRT and LCD are used as data display interfaces or data user input/output interfaces for PCs, communications terminals and various information appliances. For such displays, a screen image, for which functions that suit the usage of an information appliance are set, is displayed, for example, as a graphical user interface (GUI). Various functions, such as the arrangement of input buttons, settings for data input fields, processes to be carried out when the buttons are pressed, for example, are set for the GUI. As a programming language for developing application programs for setting the design and functions of such user interface screens, Java, which is distributed by Sun Microsystems, Inc., is used widely.
A program written in Java is converted into byte code as a computer/platform-independent Java executable file format, read by a Java virtual machine (Java VM) and converted (interpreted) into machine language and run on various apparatuses.
In Java, in order to create application software easily in a short period of time, software components that do not require re-compiling are prepared in advance, and programs are created by combining those components. In Java, a technology for making these components reusable (Java Beans) is constructed.
Components are set in units of various components such as, for example, windows to be displayed on a display, buttons, lists, combo boxes, text input fields and the like. For these components, there are defined “property” as attribute information such as, for example, shapes of buttons, position information and the like, “method” as a process as the result of an action for a component, and further “event” as a function for, when an action with respect to a component, such as the arrival of data, the occurrence of an interruption, the alteration of properties, the calling of a method or the like, occurs, communicating the event to another component. These “properties,” “methods” and “events” are taken to be elements of components in Java Beans.
The smallest executable program unit in Java is referred to as “class” and a Java Program is constituted by one or more classes. A class has a variable as data and a method as an action. It is possible to forward and store this program component that is set as a class to a PC or an information appliance through a network such as the Internet or a LAN, and on the side of the apparatus in which the class file is stored, a platform-independent Java virtual machine is able to run the program saved in the class file.
As key elements of a GUI, there are cursors and pointers. A cursor or pointer moves based on input information from, for example, a mouse, a keyboard, arrow keys of a remote control or the like as user input devices, and indicate valid input position information. In the description to follow, cursor will be used as an inclusive term for a concept that includes cursors and pointers. The displaying of cursor positions in conventional devices is commonly carried out by a bar representing a cursor, highlighting a specified area, making an icon blink and so forth.
Cursor display processes in conventional devices are of a configuration where a file that stores display image data corresponding to the cursor is set, and a display mode, such as repeated blinking patterns or specific image data display, defined for the file is executed. However, the image of such a cursor is mostly one with which a specific image data is associated, and is fixed regardless of the status of the cursor. Therefore, there is a problem in that it is hard for the user to tell the difference between whether, for example, the cursor is stationary or moving.
In addition, various information appliances can be thought of as devices in which a GUI may be implemented, but few of these would have input means that are capable of executing move instructions for a cursor freely in all directions like a mouse of a PC, and many of them carry out move control of a cursor through only the combination of move instruction keys for the four directions of up, down, left and right used in remote controls, for example, and an enter key.
When cursor move instructions based on such simple input devices are carried out, the moving of the cursor is not necessarily carried out in a linear manner with respect to the destination of the cursor movement, the cursor movement caused by user operation and the movement of the user's sight do not match, and there arises the problem of losing sight of the cursor movement, and the like.